Assessment of stockpiling methods to increase late summer and early fall forage biomass Amber Leanna Hickman Thesis submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Master of Science In Crop and Soil Environmental Sciences Azenegashe O. Abaye (Chair) Benjamin F. Tracy Christopher D. Teutsch David A. Fiske April 4, 2013 Blacksburg, Virginia Keywords: tall fescue, stockpiling, forage Copyright: Amber L. Hickman, 2013 Assessment of stockpiling methods to increase late summer and early fall forage biomass Amber L. Hickman ABSTRACT As one of the major forage crops of the United States management programs to optimize stockpiled tall fescue (Festuca arundinacea Schreb.) can potentially increase livestock profitability. This study consists of two experiments designed to assess different aspects of summer stockpiling. Experiment 1 evaluated the effects of summer stockpiling endophyte infected Kentucky 31 tall fescue on biomass and nutritive value of tall fescue forage. Treatments included four whole plot treatments (two nitrogen (N) application timing, legume inclusion, and control) each divided into sub-plot cut and no cut treatments. The cut treatment consisted of a single cutting taken in May. Nitrogen in the form of urea was applied at a rate of 56 kg/ha for the March N treatment and for the June N treatment. Yield and quality of summer stockpiled fescue was adequate to support dry beef cows. Experiment 2 evaluated the effects of summer stockpiling on the biomass yield and nutritive value of three types of tall fescue with N fertilization (endophyte infected (E+), endophyte-free (E-), and novel endophyte (MaxQ)) and four species of native warm-season grasses without N fertilization (switchgrass (Panicum virgatum L.), big bluestem (Andropogon gerardii Vitman), indiangrass (Sorghastrum nutans (L.) Nash), and little bluestem (Schizachyrium scoparium (Michx.) Nash)). Native warm-season grasses produced much higher yields than all tall fescue types but the nutritive value was not adequate to support the nutrient requirements of livestock. Summer stockpiled tall fescue is a viable resource to provide low requirement animals with quality forage during late summer and early fall. DEDICATION To my parents, Greg and Teresa Hickman, and my brother Samuel Hickman for their support, love, help, and tolerance throughout all my education. To Jeff Robinson, whose encouragement, love, and understanding is ever present. And to my sisters Samantha Cantrell and Sarah Hoffer for listening and helping me to find the humor. Thank you all for believing in me. But most importantly to my Savior who gives me the strength and constant provisions to be able to accomplish the tasks set before me. iii ACKNOWLEDGEMENTS I would like to thank all who aided in the success of this project. Below are listed just a few of the names of those who helped make this project happen. Thank you! Dr. Ozzie Abaye Dr. Ben Tracy Dr. Chris Teutsch Mr. David Fiske Dr. Mike McGilliard Dr. Amy Tanner and the Ruminant Nutrition Lab The crew at McCormick Farm Jon Wooge and the crew at Kentland Farm Agronomy Farm crew Jennifer Coleman And all those undergraduate students who have assisted in the gathering of data iv TABLE OF CONTENTS TITLE .............................................................................................................................................. i ABSTRACT .................................................................................................................................... ii DEDICATION ............................................................................................................................... iii ACKNOWLEDGEMENTS ........................................................................................................... iv TABLE OF CONTENTS ................................................................................................................ v LIST OF TABLES ....................................................................................................................... viii LIST OF FIGURES ....................................................................................................................... ix APPENDIX .................................................................................................................................... xi 1. INTRODUCTION..................................................................................................................... 1 References ................................................................................................................................... 3 2. LITERATURE REVIEW ........................................................................................................ 5 Tall Fescue .................................................................................................................................. 5 Stockpiling .................................................................................................................................. 8 The practice of winter stockpiling ........................................................................................... 9 Nitrogen Fertilization ................................................................................................................ 12 Legume Inclusion ...................................................................................................................... 15 Animal Performance ................................................................................................................. 17 Native Warm-season Grasses .................................................................................................... 19 Switchgrass................................................................................................................................ 19 Indiangrass ................................................................................................................................ 21 Big Bluestem ............................................................................................................................. 22 Little Bluestem .......................................................................................................................... 23 References ................................................................................................................................. 26 v 3. ASSESSMENT OF VARIOUS METHODS OF SUMMER STOCKPILING TALL FESCUE ....................................................................................................................................... 33 Abstract ..................................................................................................................................... 33 Introduction ............................................................................................................................... 34 Methods and Materials .............................................................................................................. 35 Forage Assessment .................................................................................................................... 37 Biomass yield ......................................................................................................................... 37 Nutritive value analysis ......................................................................................................... 38 Environmental conditions during the two experimental years .............................................. 38 Data analysis ......................................................................................................................... 39 Results and Discussion .............................................................................................................. 40 Environmental conditions during the two experimental years .............................................. 40 Total biomass yield ................................................................................................................ 41 Forage available for grazing ................................................................................................. 44 Nutritive value ....................................................................................................................... 46 Summary and Conclusions ........................................................................................................ 50 References ................................................................................................................................. 52 4. COMPARING SUMMER STOCKPILED TALL FESCUE TYPES TO NATIVE WARM-SEASON GRASSES .................................................................................................... 56 Abstract ..................................................................................................................................... 56 Introduction ............................................................................................................................... 57 Methods and Materials .............................................................................................................. 57 Data analysis ......................................................................................................................... 59 Results and Discussion .............................................................................................................. 59 Biomass yield ......................................................................................................................... 59 Nutritive value ....................................................................................................................... 61 Summary and Implications........................................................................................................ 66 References ................................................................................................................................. 68 vi 5. Summary and Conclusions .................................................................................................... 71 Appendix…………………………………………………………………………………………73 vii LIST OF TABLES 3. Assessment of various methods of summer stockpiling tall fescue: Table 3.1 Nitrogen application, cutting, and sampling dates ........................................................ 37 Table 3.2 Dates of grazing initiation, cattle removal, and pre- and post-grazing heights sampling ....................................................................................................................................................... 38 viii LIST OF FIGURES 3. Assessment of various methods of summer stockpiling tall fescue: Figure 3-1. Plot map showing treatment layouts, Shenandoah Valley AREC ............................. 36 Figure 3-2. Accumulated precipitation by month for 2011, 2012, and a 9 year historic average for Shenandoah Valley AREC ............................................................................................................ 40 Figure 3-3. Average temperature (⁰C) by month for 2011, 2012, and a 9 year historic average for Shenandoah Valley AREC ............................................................................................................ 41 Figure 3-4. Average biomass yield for use (kg/ha) by cutting treatment and year.. ..................... 43 Figure 3-5. Average biomass hay yield (kg/ha) of cut only treatments by year. .......................... 44 Figure 3-6. Average biomass yield for grazing (kg/ha) by cutting treatment. .............................. 45 Figure 3-7. Average biomass yield for grazing (kg/ha) by fertilization treatment for only the cut treatments.. .................................................................................................................................... 46 Figure 3-8. Percent neutral detergent fiber by cutting treatment and year.. ................................. 47 Figure 3-9. Percent acid detergent fiber by cutting treatment and year. ....................................... 48 Figure 3-10. Percent crude protein by fertilization treatment ....................................................... 49 Figure 3-11. Percent crude protein by cutting treatment and year. ............................................... 50 4. Comparing summer stockpiled tall fescue types to native warm-season grasses: Figure 4-1. Average biomass yield (kg/ha) by treatment for tall fescue types ............................. 60 Figure 4-2. Average biomass yield (kg/ha) by treatment for native warm-season grasses .......... 61 Figure 4-3. Percent neutral detergent fiber and acid detergent fiber by year for tall fescue types.. ....................................................................................................................................................... 62 Figure 4-4. Percent crude protein by year for tall fescue types.. .................................................. 63 Figure 4-5. Percent neutral detergent fiber by treatment and year for native warm-season grasses. ....................................................................................................................................................... 64 ix Figure 4-6. Percent acid detergent fiber by treatment and year for native warm-season grasses. ....................................................................................................................................................... 65 Figure 4-7. Percent crude protein by treatment and year for native warm-season grasses ........... 66 x